xref: /openbmc/linux/sound/soc/mxs/mxs-saif.c (revision ef2b56df)
1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License along
15  * with this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17  */
18 
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/clk.h>
27 #include <linux/clk-provider.h>
28 #include <linux/delay.h>
29 #include <linux/time.h>
30 #include <sound/core.h>
31 #include <sound/pcm.h>
32 #include <sound/pcm_params.h>
33 #include <sound/soc.h>
34 
35 #include "mxs-saif.h"
36 
37 #define MXS_SET_ADDR	0x4
38 #define MXS_CLR_ADDR	0x8
39 
40 static struct mxs_saif *mxs_saif[2];
41 
42 /*
43  * SAIF is a little different with other normal SOC DAIs on clock using.
44  *
45  * For MXS, two SAIF modules are instantiated on-chip.
46  * Each SAIF has a set of clock pins and can be operating in master
47  * mode simultaneously if they are connected to different off-chip codecs.
48  * Also, one of the two SAIFs can master or drive the clock pins while the
49  * other SAIF, in slave mode, receives clocking from the master SAIF.
50  * This also means that both SAIFs must operate at the same sample rate.
51  *
52  * We abstract this as each saif has a master, the master could be
53  * itself or other saifs. In the generic saif driver, saif does not need
54  * to know the different clkmux. Saif only needs to know who is its master
55  * and operating its master to generate the proper clock rate for it.
56  * The master id is provided in mach-specific layer according to different
57  * clkmux setting.
58  */
59 
60 static int mxs_saif_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
61 			int clk_id, unsigned int freq, int dir)
62 {
63 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
64 
65 	switch (clk_id) {
66 	case MXS_SAIF_MCLK:
67 		saif->mclk = freq;
68 		break;
69 	default:
70 		return -EINVAL;
71 	}
72 	return 0;
73 }
74 
75 /*
76  * Since SAIF may work on EXTMASTER mode, IOW, it's working BITCLK&LRCLK
77  * is provided by other SAIF, we provide a interface here to get its master
78  * from its master_id.
79  * Note that the master could be itself.
80  */
81 static inline struct mxs_saif *mxs_saif_get_master(struct mxs_saif * saif)
82 {
83 	return mxs_saif[saif->master_id];
84 }
85 
86 /*
87  * Set SAIF clock and MCLK
88  */
89 static int mxs_saif_set_clk(struct mxs_saif *saif,
90 				  unsigned int mclk,
91 				  unsigned int rate)
92 {
93 	u32 scr;
94 	int ret;
95 	struct mxs_saif *master_saif;
96 
97 	dev_dbg(saif->dev, "mclk %d rate %d\n", mclk, rate);
98 
99 	/* Set master saif to generate proper clock */
100 	master_saif = mxs_saif_get_master(saif);
101 	if (!master_saif)
102 		return -EINVAL;
103 
104 	dev_dbg(saif->dev, "master saif%d\n", master_saif->id);
105 
106 	/* Checking if can playback and capture simutaneously */
107 	if (master_saif->ongoing && rate != master_saif->cur_rate) {
108 		dev_err(saif->dev,
109 			"can not change clock, master saif%d(rate %d) is ongoing\n",
110 			master_saif->id, master_saif->cur_rate);
111 		return -EINVAL;
112 	}
113 
114 	scr = __raw_readl(master_saif->base + SAIF_CTRL);
115 	scr &= ~BM_SAIF_CTRL_BITCLK_MULT_RATE;
116 	scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
117 
118 	/*
119 	 * Set SAIF clock
120 	 *
121 	 * The SAIF clock should be either 384*fs or 512*fs.
122 	 * If MCLK is used, the SAIF clk ratio needs to match mclk ratio.
123 	 *  For 256x, 128x, 64x, and 32x sub-rates, set saif clk as 512*fs.
124 	 *  For 192x, 96x, and 48x sub-rates, set saif clk as 384*fs.
125 	 *
126 	 * If MCLK is not used, we just set saif clk to 512*fs.
127 	 */
128 	clk_prepare_enable(master_saif->clk);
129 
130 	if (master_saif->mclk_in_use) {
131 		switch (mclk / rate) {
132 		case 32:
133 		case 64:
134 		case 128:
135 		case 256:
136 		case 512:
137 			scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
138 			ret = clk_set_rate(master_saif->clk, 512 * rate);
139 			break;
140 		case 48:
141 		case 96:
142 		case 192:
143 		case 384:
144 			scr |= BM_SAIF_CTRL_BITCLK_BASE_RATE;
145 			ret = clk_set_rate(master_saif->clk, 384 * rate);
146 			break;
147 		default:
148 			/* SAIF MCLK should be a sub-rate of 512x or 384x */
149 			clk_disable_unprepare(master_saif->clk);
150 			return -EINVAL;
151 		}
152 	} else {
153 		ret = clk_set_rate(master_saif->clk, 512 * rate);
154 		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
155 	}
156 
157 	clk_disable_unprepare(master_saif->clk);
158 
159 	if (ret)
160 		return ret;
161 
162 	master_saif->cur_rate = rate;
163 
164 	if (!master_saif->mclk_in_use) {
165 		__raw_writel(scr, master_saif->base + SAIF_CTRL);
166 		return 0;
167 	}
168 
169 	/*
170 	 * Program the over-sample rate for MCLK output
171 	 *
172 	 * The available MCLK range is 32x, 48x... 512x. The rate
173 	 * could be from 8kHz to 192kH.
174 	 */
175 	switch (mclk / rate) {
176 	case 32:
177 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(4);
178 		break;
179 	case 64:
180 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
181 		break;
182 	case 128:
183 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
184 		break;
185 	case 256:
186 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
187 		break;
188 	case 512:
189 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
190 		break;
191 	case 48:
192 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(3);
193 		break;
194 	case 96:
195 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(2);
196 		break;
197 	case 192:
198 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(1);
199 		break;
200 	case 384:
201 		scr |= BF_SAIF_CTRL_BITCLK_MULT_RATE(0);
202 		break;
203 	default:
204 		return -EINVAL;
205 	}
206 
207 	__raw_writel(scr, master_saif->base + SAIF_CTRL);
208 
209 	return 0;
210 }
211 
212 /*
213  * Put and disable MCLK.
214  */
215 int mxs_saif_put_mclk(unsigned int saif_id)
216 {
217 	struct mxs_saif *saif = mxs_saif[saif_id];
218 	u32 stat;
219 
220 	if (!saif)
221 		return -EINVAL;
222 
223 	stat = __raw_readl(saif->base + SAIF_STAT);
224 	if (stat & BM_SAIF_STAT_BUSY) {
225 		dev_err(saif->dev, "error: busy\n");
226 		return -EBUSY;
227 	}
228 
229 	clk_disable_unprepare(saif->clk);
230 
231 	/* disable MCLK output */
232 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
233 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
234 	__raw_writel(BM_SAIF_CTRL_RUN,
235 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
236 
237 	saif->mclk_in_use = 0;
238 	return 0;
239 }
240 EXPORT_SYMBOL_GPL(mxs_saif_put_mclk);
241 
242 /*
243  * Get MCLK and set clock rate, then enable it
244  *
245  * This interface is used for codecs who are using MCLK provided
246  * by saif.
247  */
248 int mxs_saif_get_mclk(unsigned int saif_id, unsigned int mclk,
249 					unsigned int rate)
250 {
251 	struct mxs_saif *saif = mxs_saif[saif_id];
252 	u32 stat;
253 	int ret;
254 	struct mxs_saif *master_saif;
255 
256 	if (!saif)
257 		return -EINVAL;
258 
259 	/* Clear Reset */
260 	__raw_writel(BM_SAIF_CTRL_SFTRST,
261 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
262 
263 	/* FIXME: need clear clk gate for register r/w */
264 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
265 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
266 
267 	master_saif = mxs_saif_get_master(saif);
268 	if (saif != master_saif) {
269 		dev_err(saif->dev, "can not get mclk from a non-master saif\n");
270 		return -EINVAL;
271 	}
272 
273 	stat = __raw_readl(saif->base + SAIF_STAT);
274 	if (stat & BM_SAIF_STAT_BUSY) {
275 		dev_err(saif->dev, "error: busy\n");
276 		return -EBUSY;
277 	}
278 
279 	saif->mclk_in_use = 1;
280 	ret = mxs_saif_set_clk(saif, mclk, rate);
281 	if (ret)
282 		return ret;
283 
284 	ret = clk_prepare_enable(saif->clk);
285 	if (ret)
286 		return ret;
287 
288 	/* enable MCLK output */
289 	__raw_writel(BM_SAIF_CTRL_RUN,
290 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
291 
292 	return 0;
293 }
294 EXPORT_SYMBOL_GPL(mxs_saif_get_mclk);
295 
296 /*
297  * SAIF DAI format configuration.
298  * Should only be called when port is inactive.
299  */
300 static int mxs_saif_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt)
301 {
302 	u32 scr, stat;
303 	u32 scr0;
304 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
305 
306 	stat = __raw_readl(saif->base + SAIF_STAT);
307 	if (stat & BM_SAIF_STAT_BUSY) {
308 		dev_err(cpu_dai->dev, "error: busy\n");
309 		return -EBUSY;
310 	}
311 
312 	/* If SAIF1 is configured as slave, the clk gate needs to be cleared
313 	 * before the register can be written.
314 	 */
315 	if (saif->id != saif->master_id) {
316 		__raw_writel(BM_SAIF_CTRL_SFTRST,
317 			saif->base + SAIF_CTRL + MXS_CLR_ADDR);
318 		__raw_writel(BM_SAIF_CTRL_CLKGATE,
319 			saif->base + SAIF_CTRL + MXS_CLR_ADDR);
320 	}
321 
322 	scr0 = __raw_readl(saif->base + SAIF_CTRL);
323 	scr0 = scr0 & ~BM_SAIF_CTRL_BITCLK_EDGE & ~BM_SAIF_CTRL_LRCLK_POLARITY \
324 		& ~BM_SAIF_CTRL_JUSTIFY & ~BM_SAIF_CTRL_DELAY;
325 	scr = 0;
326 
327 	/* DAI mode */
328 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
329 	case SND_SOC_DAIFMT_I2S:
330 		/* data frame low 1clk before data */
331 		scr |= BM_SAIF_CTRL_DELAY;
332 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
333 		break;
334 	case SND_SOC_DAIFMT_LEFT_J:
335 		/* data frame high with data */
336 		scr &= ~BM_SAIF_CTRL_DELAY;
337 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
338 		scr &= ~BM_SAIF_CTRL_JUSTIFY;
339 		break;
340 	default:
341 		return -EINVAL;
342 	}
343 
344 	/* DAI clock inversion */
345 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
346 	case SND_SOC_DAIFMT_IB_IF:
347 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
348 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
349 		break;
350 	case SND_SOC_DAIFMT_IB_NF:
351 		scr |= BM_SAIF_CTRL_BITCLK_EDGE;
352 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
353 		break;
354 	case SND_SOC_DAIFMT_NB_IF:
355 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
356 		scr |= BM_SAIF_CTRL_LRCLK_POLARITY;
357 		break;
358 	case SND_SOC_DAIFMT_NB_NF:
359 		scr &= ~BM_SAIF_CTRL_BITCLK_EDGE;
360 		scr &= ~BM_SAIF_CTRL_LRCLK_POLARITY;
361 		break;
362 	}
363 
364 	/*
365 	 * Note: We simply just support master mode since SAIF TX can only
366 	 * work as master.
367 	 * Here the master is relative to codec side.
368 	 * Saif internally could be slave when working on EXTMASTER mode.
369 	 * We just hide this to machine driver.
370 	 */
371 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
372 	case SND_SOC_DAIFMT_CBS_CFS:
373 		if (saif->id == saif->master_id)
374 			scr &= ~BM_SAIF_CTRL_SLAVE_MODE;
375 		else
376 			scr |= BM_SAIF_CTRL_SLAVE_MODE;
377 
378 		__raw_writel(scr | scr0, saif->base + SAIF_CTRL);
379 		break;
380 	default:
381 		return -EINVAL;
382 	}
383 
384 	return 0;
385 }
386 
387 static int mxs_saif_startup(struct snd_pcm_substream *substream,
388 			   struct snd_soc_dai *cpu_dai)
389 {
390 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
391 
392 	/* clear error status to 0 for each re-open */
393 	saif->fifo_underrun = 0;
394 	saif->fifo_overrun = 0;
395 
396 	/* Clear Reset for normal operations */
397 	__raw_writel(BM_SAIF_CTRL_SFTRST,
398 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
399 
400 	/* clear clock gate */
401 	__raw_writel(BM_SAIF_CTRL_CLKGATE,
402 		saif->base + SAIF_CTRL + MXS_CLR_ADDR);
403 
404 	clk_prepare(saif->clk);
405 
406 	return 0;
407 }
408 
409 static void mxs_saif_shutdown(struct snd_pcm_substream *substream,
410 			      struct snd_soc_dai *cpu_dai)
411 {
412 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
413 
414 	clk_unprepare(saif->clk);
415 }
416 
417 /*
418  * Should only be called when port is inactive.
419  * although can be called multiple times by upper layers.
420  */
421 static int mxs_saif_hw_params(struct snd_pcm_substream *substream,
422 			     struct snd_pcm_hw_params *params,
423 			     struct snd_soc_dai *cpu_dai)
424 {
425 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
426 	struct mxs_saif *master_saif;
427 	u32 scr, stat;
428 	int ret;
429 
430 	master_saif = mxs_saif_get_master(saif);
431 	if (!master_saif)
432 		return -EINVAL;
433 
434 	/* mclk should already be set */
435 	if (!saif->mclk && saif->mclk_in_use) {
436 		dev_err(cpu_dai->dev, "set mclk first\n");
437 		return -EINVAL;
438 	}
439 
440 	stat = __raw_readl(saif->base + SAIF_STAT);
441 	if (!saif->mclk_in_use && (stat & BM_SAIF_STAT_BUSY)) {
442 		dev_err(cpu_dai->dev, "error: busy\n");
443 		return -EBUSY;
444 	}
445 
446 	/*
447 	 * Set saif clk based on sample rate.
448 	 * If mclk is used, we also set mclk, if not, saif->mclk is
449 	 * default 0, means not used.
450 	 */
451 	ret = mxs_saif_set_clk(saif, saif->mclk, params_rate(params));
452 	if (ret) {
453 		dev_err(cpu_dai->dev, "unable to get proper clk\n");
454 		return ret;
455 	}
456 
457 	if (saif != master_saif) {
458 		/*
459 		* Set an initial clock rate for the saif internal logic to work
460 		* properly. This is important when working in EXTMASTER mode
461 		* that uses the other saif's BITCLK&LRCLK but it still needs a
462 		* basic clock which should be fast enough for the internal
463 		* logic.
464 		*/
465 		clk_enable(saif->clk);
466 		ret = clk_set_rate(saif->clk, 24000000);
467 		clk_disable(saif->clk);
468 		if (ret)
469 			return ret;
470 
471 		clk_prepare(master_saif->clk);
472 	}
473 
474 	scr = __raw_readl(saif->base + SAIF_CTRL);
475 
476 	scr &= ~BM_SAIF_CTRL_WORD_LENGTH;
477 	scr &= ~BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
478 	switch (params_format(params)) {
479 	case SNDRV_PCM_FORMAT_S16_LE:
480 		scr |= BF_SAIF_CTRL_WORD_LENGTH(0);
481 		break;
482 	case SNDRV_PCM_FORMAT_S20_3LE:
483 		scr |= BF_SAIF_CTRL_WORD_LENGTH(4);
484 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
485 		break;
486 	case SNDRV_PCM_FORMAT_S24_LE:
487 		scr |= BF_SAIF_CTRL_WORD_LENGTH(8);
488 		scr |= BM_SAIF_CTRL_BITCLK_48XFS_ENABLE;
489 		break;
490 	default:
491 		return -EINVAL;
492 	}
493 
494 	/* Tx/Rx config */
495 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
496 		/* enable TX mode */
497 		scr &= ~BM_SAIF_CTRL_READ_MODE;
498 	} else {
499 		/* enable RX mode */
500 		scr |= BM_SAIF_CTRL_READ_MODE;
501 	}
502 
503 	__raw_writel(scr, saif->base + SAIF_CTRL);
504 	return 0;
505 }
506 
507 static int mxs_saif_prepare(struct snd_pcm_substream *substream,
508 			   struct snd_soc_dai *cpu_dai)
509 {
510 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
511 
512 	/* enable FIFO error irqs */
513 	__raw_writel(BM_SAIF_CTRL_FIFO_ERROR_IRQ_EN,
514 		saif->base + SAIF_CTRL + MXS_SET_ADDR);
515 
516 	return 0;
517 }
518 
519 static int mxs_saif_trigger(struct snd_pcm_substream *substream, int cmd,
520 				struct snd_soc_dai *cpu_dai)
521 {
522 	struct mxs_saif *saif = snd_soc_dai_get_drvdata(cpu_dai);
523 	struct mxs_saif *master_saif;
524 	u32 delay;
525 	int ret;
526 
527 	master_saif = mxs_saif_get_master(saif);
528 	if (!master_saif)
529 		return -EINVAL;
530 
531 	switch (cmd) {
532 	case SNDRV_PCM_TRIGGER_START:
533 	case SNDRV_PCM_TRIGGER_RESUME:
534 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
535 		if (saif->state == MXS_SAIF_STATE_RUNNING)
536 			return 0;
537 
538 		dev_dbg(cpu_dai->dev, "start\n");
539 
540 		ret = clk_enable(master_saif->clk);
541 		if (ret) {
542 			dev_err(saif->dev, "Failed to enable master clock\n");
543 			return ret;
544 		}
545 
546 		/*
547 		 * If the saif's master is not itself, we also need to enable
548 		 * itself clk for its internal basic logic to work.
549 		 */
550 		if (saif != master_saif) {
551 			ret = clk_enable(saif->clk);
552 			if (ret) {
553 				dev_err(saif->dev, "Failed to enable master clock\n");
554 				clk_disable(master_saif->clk);
555 				return ret;
556 			}
557 
558 			__raw_writel(BM_SAIF_CTRL_RUN,
559 				saif->base + SAIF_CTRL + MXS_SET_ADDR);
560 		}
561 
562 		if (!master_saif->mclk_in_use)
563 			__raw_writel(BM_SAIF_CTRL_RUN,
564 				master_saif->base + SAIF_CTRL + MXS_SET_ADDR);
565 
566 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
567 			/*
568 			 * write data to saif data register to trigger
569 			 * the transfer.
570 			 * For 24-bit format the 32-bit FIFO register stores
571 			 * only one channel, so we need to write twice.
572 			 * This is also safe for the other non 24-bit formats.
573 			 */
574 			__raw_writel(0, saif->base + SAIF_DATA);
575 			__raw_writel(0, saif->base + SAIF_DATA);
576 		} else {
577 			/*
578 			 * read data from saif data register to trigger
579 			 * the receive.
580 			 * For 24-bit format the 32-bit FIFO register stores
581 			 * only one channel, so we need to read twice.
582 			 * This is also safe for the other non 24-bit formats.
583 			 */
584 			__raw_readl(saif->base + SAIF_DATA);
585 			__raw_readl(saif->base + SAIF_DATA);
586 		}
587 
588 		master_saif->ongoing = 1;
589 		saif->state = MXS_SAIF_STATE_RUNNING;
590 
591 		dev_dbg(saif->dev, "CTRL 0x%x STAT 0x%x\n",
592 			__raw_readl(saif->base + SAIF_CTRL),
593 			__raw_readl(saif->base + SAIF_STAT));
594 
595 		dev_dbg(master_saif->dev, "CTRL 0x%x STAT 0x%x\n",
596 			__raw_readl(master_saif->base + SAIF_CTRL),
597 			__raw_readl(master_saif->base + SAIF_STAT));
598 		break;
599 	case SNDRV_PCM_TRIGGER_SUSPEND:
600 	case SNDRV_PCM_TRIGGER_STOP:
601 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
602 		if (saif->state == MXS_SAIF_STATE_STOPPED)
603 			return 0;
604 
605 		dev_dbg(cpu_dai->dev, "stop\n");
606 
607 		/* wait a while for the current sample to complete */
608 		delay = USEC_PER_SEC / master_saif->cur_rate;
609 
610 		if (!master_saif->mclk_in_use) {
611 			__raw_writel(BM_SAIF_CTRL_RUN,
612 				master_saif->base + SAIF_CTRL + MXS_CLR_ADDR);
613 			udelay(delay);
614 		}
615 		clk_disable(master_saif->clk);
616 
617 		if (saif != master_saif) {
618 			__raw_writel(BM_SAIF_CTRL_RUN,
619 				saif->base + SAIF_CTRL + MXS_CLR_ADDR);
620 			udelay(delay);
621 			clk_disable(saif->clk);
622 		}
623 
624 		master_saif->ongoing = 0;
625 		saif->state = MXS_SAIF_STATE_STOPPED;
626 
627 		break;
628 	default:
629 		return -EINVAL;
630 	}
631 
632 	return 0;
633 }
634 
635 #define MXS_SAIF_RATES		SNDRV_PCM_RATE_8000_192000
636 #define MXS_SAIF_FORMATS \
637 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE | \
638 	SNDRV_PCM_FMTBIT_S24_LE)
639 
640 static const struct snd_soc_dai_ops mxs_saif_dai_ops = {
641 	.startup = mxs_saif_startup,
642 	.shutdown = mxs_saif_shutdown,
643 	.trigger = mxs_saif_trigger,
644 	.prepare = mxs_saif_prepare,
645 	.hw_params = mxs_saif_hw_params,
646 	.set_sysclk = mxs_saif_set_dai_sysclk,
647 	.set_fmt = mxs_saif_set_dai_fmt,
648 };
649 
650 static int mxs_saif_dai_probe(struct snd_soc_dai *dai)
651 {
652 	struct mxs_saif *saif = dev_get_drvdata(dai->dev);
653 
654 	snd_soc_dai_set_drvdata(dai, saif);
655 
656 	return 0;
657 }
658 
659 static struct snd_soc_dai_driver mxs_saif_dai = {
660 	.name = "mxs-saif",
661 	.probe = mxs_saif_dai_probe,
662 	.playback = {
663 		.channels_min = 2,
664 		.channels_max = 2,
665 		.rates = MXS_SAIF_RATES,
666 		.formats = MXS_SAIF_FORMATS,
667 	},
668 	.capture = {
669 		.channels_min = 2,
670 		.channels_max = 2,
671 		.rates = MXS_SAIF_RATES,
672 		.formats = MXS_SAIF_FORMATS,
673 	},
674 	.ops = &mxs_saif_dai_ops,
675 };
676 
677 static const struct snd_soc_component_driver mxs_saif_component = {
678 	.name		= "mxs-saif",
679 };
680 
681 static irqreturn_t mxs_saif_irq(int irq, void *dev_id)
682 {
683 	struct mxs_saif *saif = dev_id;
684 	unsigned int stat;
685 
686 	stat = __raw_readl(saif->base + SAIF_STAT);
687 	if (!(stat & (BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ |
688 			BM_SAIF_STAT_FIFO_OVERFLOW_IRQ)))
689 		return IRQ_NONE;
690 
691 	if (stat & BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ) {
692 		dev_dbg(saif->dev, "underrun!!! %d\n", ++saif->fifo_underrun);
693 		__raw_writel(BM_SAIF_STAT_FIFO_UNDERFLOW_IRQ,
694 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
695 	}
696 
697 	if (stat & BM_SAIF_STAT_FIFO_OVERFLOW_IRQ) {
698 		dev_dbg(saif->dev, "overrun!!! %d\n", ++saif->fifo_overrun);
699 		__raw_writel(BM_SAIF_STAT_FIFO_OVERFLOW_IRQ,
700 				saif->base + SAIF_STAT + MXS_CLR_ADDR);
701 	}
702 
703 	dev_dbg(saif->dev, "SAIF_CTRL %x SAIF_STAT %x\n",
704 	       __raw_readl(saif->base + SAIF_CTRL),
705 	       __raw_readl(saif->base + SAIF_STAT));
706 
707 	return IRQ_HANDLED;
708 }
709 
710 static int mxs_saif_mclk_init(struct platform_device *pdev)
711 {
712 	struct mxs_saif *saif = platform_get_drvdata(pdev);
713 	struct device_node *np = pdev->dev.of_node;
714 	struct clk *clk;
715 	int ret;
716 
717 	clk = clk_register_divider(&pdev->dev, "mxs_saif_mclk",
718 				   __clk_get_name(saif->clk), 0,
719 				   saif->base + SAIF_CTRL,
720 				   BP_SAIF_CTRL_BITCLK_MULT_RATE, 3,
721 				   0, NULL);
722 	if (IS_ERR(clk)) {
723 		ret = PTR_ERR(clk);
724 		if (ret == -EEXIST)
725 			return 0;
726 		dev_err(&pdev->dev, "failed to register mclk: %d\n", ret);
727 		return PTR_ERR(clk);
728 	}
729 
730 	ret = of_clk_add_provider(np, of_clk_src_simple_get, clk);
731 	if (ret)
732 		return ret;
733 
734 	return 0;
735 }
736 
737 static int mxs_saif_probe(struct platform_device *pdev)
738 {
739 	struct device_node *np = pdev->dev.of_node;
740 	struct resource *iores;
741 	struct mxs_saif *saif;
742 	int irq, ret = 0;
743 	struct device_node *master;
744 
745 	if (!np)
746 		return -EINVAL;
747 
748 	saif = devm_kzalloc(&pdev->dev, sizeof(*saif), GFP_KERNEL);
749 	if (!saif)
750 		return -ENOMEM;
751 
752 	ret = of_alias_get_id(np, "saif");
753 	if (ret < 0)
754 		return ret;
755 	else
756 		saif->id = ret;
757 
758 	if (saif->id >= ARRAY_SIZE(mxs_saif)) {
759 		dev_err(&pdev->dev, "get wrong saif id\n");
760 		return -EINVAL;
761 	}
762 
763 	/*
764 	 * If there is no "fsl,saif-master" phandle, it's a saif
765 	 * master.  Otherwise, it's a slave and its phandle points
766 	 * to the master.
767 	 */
768 	master = of_parse_phandle(np, "fsl,saif-master", 0);
769 	if (!master) {
770 		saif->master_id = saif->id;
771 	} else {
772 		ret = of_alias_get_id(master, "saif");
773 		if (ret < 0)
774 			return ret;
775 		else
776 			saif->master_id = ret;
777 
778 		if (saif->master_id >= ARRAY_SIZE(mxs_saif)) {
779 			dev_err(&pdev->dev, "get wrong master id\n");
780 			return -EINVAL;
781 		}
782 	}
783 
784 	mxs_saif[saif->id] = saif;
785 
786 	saif->clk = devm_clk_get(&pdev->dev, NULL);
787 	if (IS_ERR(saif->clk)) {
788 		ret = PTR_ERR(saif->clk);
789 		dev_err(&pdev->dev, "Cannot get the clock: %d\n",
790 			ret);
791 		return ret;
792 	}
793 
794 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
795 
796 	saif->base = devm_ioremap_resource(&pdev->dev, iores);
797 	if (IS_ERR(saif->base))
798 		return PTR_ERR(saif->base);
799 
800 	irq = platform_get_irq(pdev, 0);
801 	if (irq < 0) {
802 		ret = irq;
803 		dev_err(&pdev->dev, "failed to get irq resource: %d\n",
804 			ret);
805 		return ret;
806 	}
807 
808 	saif->dev = &pdev->dev;
809 	ret = devm_request_irq(&pdev->dev, irq, mxs_saif_irq, 0,
810 			       dev_name(&pdev->dev), saif);
811 	if (ret) {
812 		dev_err(&pdev->dev, "failed to request irq\n");
813 		return ret;
814 	}
815 
816 	platform_set_drvdata(pdev, saif);
817 
818 	/* We only support saif0 being tx and clock master */
819 	if (saif->id == 0) {
820 		ret = mxs_saif_mclk_init(pdev);
821 		if (ret)
822 			dev_warn(&pdev->dev, "failed to init clocks\n");
823 	}
824 
825 	ret = devm_snd_soc_register_component(&pdev->dev, &mxs_saif_component,
826 					      &mxs_saif_dai, 1);
827 	if (ret) {
828 		dev_err(&pdev->dev, "register DAI failed\n");
829 		return ret;
830 	}
831 
832 	ret = mxs_pcm_platform_register(&pdev->dev);
833 	if (ret) {
834 		dev_err(&pdev->dev, "register PCM failed: %d\n", ret);
835 		return ret;
836 	}
837 
838 	return 0;
839 }
840 
841 static const struct of_device_id mxs_saif_dt_ids[] = {
842 	{ .compatible = "fsl,imx28-saif", },
843 	{ /* sentinel */ }
844 };
845 MODULE_DEVICE_TABLE(of, mxs_saif_dt_ids);
846 
847 static struct platform_driver mxs_saif_driver = {
848 	.probe = mxs_saif_probe,
849 
850 	.driver = {
851 		.name = "mxs-saif",
852 		.of_match_table = mxs_saif_dt_ids,
853 	},
854 };
855 
856 module_platform_driver(mxs_saif_driver);
857 
858 MODULE_AUTHOR("Freescale Semiconductor, Inc.");
859 MODULE_DESCRIPTION("MXS ASoC SAIF driver");
860 MODULE_LICENSE("GPL");
861 MODULE_ALIAS("platform:mxs-saif");
862